In recent years, research and development of an organic thin film transistor element utilizing an organic semiconductor material has been actively carried out for a technique to make up for disadvantage of an thin film transistor (hereinafter also referred to as TFT) element utilizing a conventional silicon material (refer to Patent Document 1, Non-patent Document 1 and the like).
The organic TFT element can be manufactured by a low temperature manufacturing process, and enables use of a resin substrate which is difficult to break and light. Further, the organic TFT element is considered to enable to realize a flexible display employing a resin film as a support member (refer to Non-Patent Document 2 and the like).
Further, in recent years, many methods have been proposed in which a TFT, for use as a pixel driving element, for example, is manufactured under atmospheric pressure, employing a coating apparatus represented by an ink jet process for the purpose of high productivity and reduction of manufacturing cost. For example, there is disclosed a technique in which, in the process of forming a TFT for a liquid crystal panel or an organic EL (Electro Luminescence) panel used as display device, a droplet of a semiconductor liquid in which a semiconductor material is dissolved or dispersed in a solvent is jetted and sequentially applied onto a substrate employing a coating apparatus to form a semiconductor layer (refer to Patent Document 2).
It is necessary that the TFT for driving pixels in a display panel be formed on a substrate in the form of a matrix at the same interval as in the pixel alignment. During a process of forming a TFT, a head, in which nozzles for jetting the semiconductor liquid are aligned in a line, is moved on a substrate, so that the semiconductor liquid is sequentially jetted from the nozzles onto the substrate. The solvent of the semiconductor liquid jetted onto the substrate is gradually vaporized, in which, as the concentration of the semiconductor liquid increases, the semiconductor crystal of the semiconductor material grows. Thus, a semiconductor layer for a TFT is formed.    Patent Document 1: Japanese Patent O.P.I. Publication No. 10-190001    Patent Document 2: Japanese Patent O.P.I. Publication No. 2007-243081    Non-Patent Document 1: Advanced Material, 2002, No. 2, page. 99 (Review)    Non-Patent Document 2: SID '01 Digest page 57